Inlarged nipples after first heat

Question
I have a female golden who finished her first heat about a month ago, as well as a male who we kept well separated during heat.  We used the diaper on the female during heat and are 99 percent sure there was no contact to avoid her getting pregnant to early.  We due intend to breed but not till the female is around 3.  However her nipples have gotten quite large and has what appears to be small fatty type tissue around each nipple... the question is, is this normal for a females nipples to get bigger after first heat just like puberty in humans, or is there a potential that she is "with pups"?...... thank you in advance

Answer
It sounds normal, I wouldn't be concerned about it.  I am concerned you are planning on breeding without having learned the answer to that and a thousand other questions.  Your question suggest to me you are much too low on the dog learning curve to be breeding. No large breed dog should be bred without hip X-rays first. This gives you time for extensive study.  To understand what I am saying about the study you need to do before breeding dogs see http://www.woodhavenlabs.com/articles.html#breeding

Successful Dog Breeding, by Chris Walkowicz, DMV comes highly recommended .

Please don't add to the misery resulting from others lacking the knowledge to breed quality dogs.